Early Eurasian migration traces in the Tarim Basin revealed by mtDNA polymorphisms

The mitochondrial DNA (mtDNA) polymorphisms of 58 samples from the Daheyan village located in the central Taklamakan Desert of the Tarim Basin were determined in this study. Among the 58 samples, 29 haplotypes belonging to 18 different haplogroups were analyzed. Almost all the mtDNAs belong to a subset of either the defined Western or Eastern Eurasian pool. Extensive Eastern Eurasian lineages exist in the Daheyan population in which Northern‐prevalent haplogroups present higher frequencies. In the limited existing Western Eurasian lineages, two sub‐haplogroups, U3 and X2, that are rare in Central Asia were found in this study, which may be indicative of the remnants of an early immigrant population from the Near East and Caucasus regions preserved only in the Tarim Basin. The presence of U3 in modern and archeological samples in the Tarim Basin suggests that the immigration took place earlier than 2,000 years ago and points to human continuity in this area, with at least one Western lineage originating from the Near East and Caucasus regions. Am J Phys Anthropol 142:558–564, 2010. © 2010 Wiley‐Liss, Inc.     

Mitochondrial DNA structure in North Africa reveals a genetic discontinuity in the Nile Valley

Human population movements in North Africa have been mostly restricted to an east-west direction due to the geographical barriers imposed by the Sahara Desert and the Mediterranean Sea. Although these barriers have not completely impeded human migrations, genetic studies have shown that an east-west genetic gradient exists. However, the lack of genetic information of certain geographical areas and the focus of some studies in parts of the North African landscape have limited the global view of the genetic pool of North African populations. To provide a global view of the North African genetic landscape and population structure, we have analyzed ～2,300 North African mitochondrial DNA lineages (including 269 new sequences from Libya, in the first mtDNA study of the general Libyan population). Our results show a clinal distribution of certain haplogroups, some of them more frequent in Western (H, HV0, L1b, L3b, U6) or Eastern populations (L0a, R0a, N1b, I, J) that might be the result of human migrations from the Middle East, sub-Saharan Africa, and Europe. Despite this clinal pattern, a genetic discontinuity is found in the Libyan/Egyptian border, suggesting a differential gene flow in the Nile River Valley. Finally, frequency of the post-LGM subclades H1 and H3 is predominant in Libya within the H sequences, highlighting the magnitude of the LGM expansion in North Africa.     

Phylogeography,genetic diversity and demographic history of the Iranian Kurdish groups based on mtDNA sequences

Throughout the history of modern humans, the current Kurdish-inhabited area has served as part of a tricontinental crossroad for major human migrations. Also, a significant body of archaeological evidence points to this area as the site of Neolithic transition. To investigate the phylogeography, origins and demographic history, mtDNA D-loop region of individuals representing four Kurdish groups from Iran were analysed. Our data indicated that most of the Kurds mtDNA lineages belong to branches of the haplogroups with the Western Eurasian origin; with small fractions of the Eastern Eurasian and sub-Saharan African lineages. The low level of mtDNA diversity observed in the Havrami group presented a bias towards isolation or increased drift due to small population size; while in the Kurmanji group it indicated a bias towards drift or mass migration events during the 5–18th century AD. The Mantel test showed strong isolation by distance, and AMOVA results for global and regional scales confirmed that the geography had acted as the main driving force in shaping the current pattern of mtDNA diversity, rather than linguistic similarity. The results of demographic analyses, in agreement with archaeological data, revealed a recent expansion of the Kurds (～9,500 years before present) related to the Neolithic transition from hunting and gathering, to farming and cattle breeding in the Near East. Further, the high frequencies of typical haplogroups for early farmers (H; 37.1%) and hunter-gatherers (U; 13.8%) in the Kurds may testify the earlier hunter-gatherers in the Kurdish-inhabited area that adopted and admixed the Kurds ancestors following the Neolithic transition.     

High levels of Paleolithic Y-chromosome lineages characterize Serbia

Whether present-day European genetic variation and its distribution patterns can be attributed primarily to the initial peopling of Europe by anatomically modern humans during the Paleolithic, or to latter Near Eastern Neolithic input is still the subject of debate. Southeastern Europe has been a crossroads for several cultures since Paleolithic times and the Balkans, specifically, would have been part of the route used by Neolithic farmers to enter Europe. Given its geographic location in the heart of the Balkan Peninsula at the intersection of Central and Southeastern Europe, Serbia represents a key geographical location that may provide insight to elucidate the interactions between indigenous Paleolithic people and agricultural colonists from the Fertile Crescent. In this study, we examine, for the first time, the Y-chromosome constitution of the general Serbian population. A total of 103 individuals were sampled and their DNA analyzed for 104 Y-chromosome bi-allelic markers and 17 associated STR loci. Our results indicate that approximately 58% of Serbian Y-chromosomes (I1-M253, I2a-P37.2 and R1a1a-M198) belong to lineages believed to be pre-Neolithic. On the other hand, the signature of putative Near Eastern Neolithic lineages, including E1b1b1a1-M78, G2a-P15, J1-M267, J2-M172 and R1b1a2-M269 accounts for 39% of the Y-chromosome. Haplogroup frequency distributions in Western and Eastern Europe reveal a spotted landscape of paleolithic Y chromosomes, undermining continental-wide generalizations. Furthermore, an examination of the distribution of Y-chromosome filiations in Europe indicates extreme levels of Paleolithic lineages in a region encompassing Serbia, Bosnia-Herzegovina and Croatia, possibly the result of Neolithic migrations encroaching on Paleolithic populations against the Adriatic Sea.     

Increased resolution of Y chromosome haplogroup T defines relationships among populations of the Near East, Europe, and Africa

Increasing phylogenetic resolution of the Y chromosome haplogroup tree has led to finer temporal and spatial resolution for studies of human migration. Haplogroup T, initially known as K2 and defined by mutation M70, is found at variable frequencies across West Asia, Africa, and Europe. While several SNPs were recently discovered that extended the length of the branch leading to haplogroup T, only two SNPs are known to mark internal branches of haplogroup T. This low level of phylogenetic resolution has hindered studies of the origin and dispersal of this interesting haplogroup, which is found in Near Eastern non-Jewish populations, Jewish populations from several communities, and in the patrilineage of President Thomas Jefferson. Here we map 10 new SNPs that, together with the previously known SNPs, mark 11 lineages and two large subclades (T1a and T1b) of haplogroup T. We also report a new SNP that links haplogroups T and L within the major framework of Y chromosome evolution. Estimates of the timing of the branching events within haplogroup T, along with a comprehensive geographic survey of the major T subclades, suggest that this haplogroup began to diversify in the Near East -25 kya. Our survey also points to a complex history of dispersal of this rare and informative haplogroup within the Near East and from the Near East to Europe and sub-Saharan Africa. The presence of T1a2 chromosomes in Near Eastern Jewish and non-Jewish populations may reflect early exiles between the ancient lands of Israel and Babylon. The presence of different subclades of T chromosomes in Europe may be explained by both the spread of Neolithic farmers and the later dispersal of Jews from the Near East. Finally, the moderately high frequency (-18%) of T1b* chromosomes in the Lemba of southern Africa supports the hypothesis of a Near Eastern, but not necessarily a Jewish, origin for their paternal line.     

Tracing European founder lineages in the Near Eastern mtDNA pool

Founder analysis is a method for analysis of nonrecombining DNA sequence data, with the aim of identification and dating of migrations into new territory. The method picks out founder sequence types in potential source populations and dates lineage clusters deriving from them in the settlement zone of interest. Here, using mtDNA, we apply the approach to the colonization of Europe, to estimate the proportion of modern lineages whose ancestors arrived during each major phase of settlement. To estimate the Palaeolithic and Neolithic contributions to European mtDNA diversity more accurately than was previously achievable, we have now extended the Near Eastern, European, and northern-Caucasus databases to 1,234, 2, 804, and 208 samples, respectively. Both back-migration into the source population and recurrent mutation in the source and derived populations represent major obstacles to this approach. We have developed phylogenetic criteria to take account of both these factors, and we suggest a way to account for multiple dispersals of common sequence types. We conclude that (i) there has been substantial back-migration into the Near East, (ii) the majority of extant mtDNA lineages entered Europe in several waves during the Upper Palaeolithic, (iii) there was a founder effect or bottleneck associated with the Last Glacial Maximum, 20,000 years ago, from which derives the largest fraction of surviving lineages, and (iv) the immigrant Neolithic component is likely to comprise less than one-quarter of the mtDNA pool of modern Europeans.     

African DNA lineages in mitochondrial gene pool of Europeans

Mitochondrial DNA (mtDNA) nucleotide sequences of African origin have been found at low frequency (1%, in average) in different European populations. In the present study, data on mtDNA variability in populations of Eurasia and Africa are analyzed and search of African-specific lineages present in Europeans is conducted. The results of analysis indicate that, despite a high diversity of African mtDNA haplotypes found in Europeans, monophyletic clusters of African mtDNA lineages, arisen in Europe and characterized by long-term diversity, are nearly absent in Europe. Only two respective clusters (belonging to haplogroups L1b and L3b), which evolutionary age does not exceed 6.5 thousands years, were revealed. Comparative analysis of distribution of frequencies of autosomal microsatellite alleles found in Russian individuals, carrying the African-specific mitochondrial haplotypes, in populations of Europe and Africa has indicated that autosomal genotypes of those Russian individuals are characterized by the presence of alleles characteristic mostly for Europeans.     

Mitochondrial DNA affinities at the Atlantic fringe of Europe

Mitochondrial DNA analysis of Atlantic European samples has detected significant latitudinal clines for several clusters with Paleolithic (H) and Neolithic (J, U4, U5a1, and U5a1a) coalescence ages in Europe. These gradients may be explained as the result of Neolithic influence on a rather homogeneous Paleolithic background. There is also evidence that some Neolithic clusters reached this border by a continental route (J, J1, J1a, U5a1, and U5a1a), whereas others (J2) did so through the Mediterranean coast. An important gene flow from Africa was detected in the Atlantic Iberia. Specific sub-Saharan lineages appeared mainly restricted to southern Portugal, and could be attributed to historic Black slave trade in the area and to a probable Saharan Neolithic influence. In fact, U6 haplotypes of specific North African origin have only been detected in the Iberian peninsula northwards from central Portugal. Based on this peculiar distribution and the high diversity pi value (0.014 +/- 0.001) in this area compared to North Africa (0.006 +/- 0.001), we reject the proposal that only historic events such as the Moslem occupation are the main cause of this gene flow, and instead propose a pre-Neolithic origin for it.     

Estimating the impact of prehistoric admixture on the genome of Europeans

We inferred past admixture processes in the European population from genetic diversity at eight loci, including autosomal, mitochondrial and Y-linked polymorphisms. Admixture coefficients were estimated from multilocus data, assuming that most current populations can be regarded as the result of a hybridization process among four or less potential parental populations. Two main components are apparent in the Europeans' genome, presumably corresponding to the contributions of the first, Paleolithic Europeans, and of the early, Neolithic farmers dispersing from the Near East. In addition, only a small fraction of the European alleles seems to come from North Africa, and a fourth component reflecting gene flow from Northern Asia is largely restricted to the northeast of the continent. The estimated Near Eastern contribution decreases as one moves from east to west, in agreement with the predictions of a model in which (Neolithic) immigrants from the Near East contributed a large share of the alleles in the genome of current Europeans. Several tests suggest that probable departures from the admixture models, due to factors such as choice of the putative parental populations and more complex demographic scenarios, may have affected our main estimates only to a limited extent.     

Maternal genomic variability of the wild boar (Sus scrofa) reveals the uniqueness of East‐Caucasian and Central Italian populations

The phylogeography of the European wild boar was mainly determined by postglacial recolonization patterns from Mediterranean refugia after the last ice age. Here we present the first analysis of SNP polymorphism within the complete mtDNA genome of West Russian (n = 8), European (n = 64), and North African (n = 5) wild boar. Our analyses provided evidence of unique lineages in the East‐Caucasian (Dagestan) region and in Central Italy. A phylogenetic analysis revealed that these lineages are basal to the other European mtDNA sequences. We also show close connection between the Western Siberian and Eastern European populations. Also, the North African samples were clustered with the Iberian population. Phylogenetic trees and migration modeling revealed a high proximity of Dagestan sequences to those of Central Italy and suggested possible gene flow between Western Asia and Southern Europe which was not directly related to Northern and Central European lineages. Our results support the presence of old maternal lineages in two Southern glacial refugia (i.e., Caucasus and the Italian peninsula), as a legacy of an ancient wave of colonization of Southern Europe from an Eastern origin.     

A genetic analysis of the Sakishima islanders reveals no relationship with Taiwan aborigines but shared ancestry with Ainu and main‐island Japanese

The Sakishima islands are members of the Ryukyu island chain, stretching from the southwestern tip of the Japanese archipelago to Taiwan in the East China Sea. Archaeological data indicate cultural similarities between inhabitants of prehistoric Sakishima and Neolithic Taiwan. Recent studies based on tooth crown traits show remarkably high inter‐island diversity among Ryukyu islanders, suggesting that the Sakishima islanders might have genetic backgrounds distinct from main‐island Okinawa people. To investigate the genetic diversity of the Ryukyu islanders, we analyzed mtDNA, Y chromosome, and autosomal short tandem repeat loci in a sample of main‐island Okinawa people and Sakishima (Miyako and Ishigaki) islanders whose participated in a previous study of tooth crown morphology. Our phylogenetic analysis of maternal (mtDNA) and paternal (Y chromosome) lineages shows that the Sakishima islanders are more closely related to people from the Japanese archipelago than to Taiwan aborigines. Miyako islanders and the Hokkaido Ainu have the first and second highest frequencies (respectively) of the Y‐chromosomal Alu‐insertion polymorphism, which is a presumable Jomon marker. Genetic diversity statistics show no evidence of demographic reduction or of extreme isolation in each island's population. Thus, we conclude that 1) Neolithic expansion from Taiwan did not contribute to the gene pool of modern Sakishima islanders, 2) male‐lineage of the Ryukyu islanders likely shares a common ancestor with the Hokkaido Ainu who are presumably direct descendants of the Jomon people, and 3) frequent reciprocal gene flow among islands has masked the trace of common ancestry in the Ryukyu island chain. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.     

Post‐last glacial maximum expansion from Iberia to North Africa revealed by fine characterization of mtDNA H haplogroup in Tunisia

The first large‐scale fine characterization of Tunisian H lineages clarifies that the post‐Last glacial maximum expansion originating in Iberia not only led to the resettlement of Europe but also of North Africa. We found that 46% of 81 Tunisian H lineages subscreened for 1,580 bp in mtDNA coding region were affiliated with H1 and H3 subhaplogroups, which are known to have originated in Iberia. Although no signs of local expansion were detected, which would allow a clear dating of their introduction, the younger and less diverse Tunisian H1 and H3 lineages indicate Iberia as the radiating centre. Major contributions from historical migrations to this Iberian genetic imprint in Tunisia were ruled out by the mtDNA gene pool similarity between Berber/Arab/cosmopolitan samples and some “Andalusian” communities, settled by the descendents of the “Moors” who once lived in Iberia for 10 centuries (between 8th and 17th centuries), before being expelled to Tunisia. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.     

Pleistocene-Holocene boundary in Southern Arabia from the perspective of human mtDNA variation

It is now known that several population movements have taken place at different times throughout southern Arabian prehistory. One of the principal questions under debate is if the Early Holocene peopling of southern Arabia was mainly due to input from the Levant during the Pre‐Pottery Neolithic B, to the expansion of an autochthonous population, or some combination of these demographic processes. Since previous genetic studies have not been able to include all parts of southern Arabia, we have helped fill this lacuna by collecting new population datasets from Oman (Dhofar) and Yemen (Al‐Mahra and Bab el‐Mandab). We identified several new haplotypes belonging to haplogroup R2 and generated its whole genome mtDNA tree with age estimates undertaken by different methods. R2, together with other considerably frequent southern Arabian mtDNA haplogroups (R0a, HV1, summing up more than 20% of the South Arabian gene pool) were used to infer the past effective population size through Bayesian skyline plots. These data indicate that the southern Arabian population underwent a large expansion already some 12 ka. A founder analysis of these haplogroups shows that this expansion is largely attributed to demographic input from the Near East. These results support thus the spread of a population coming from the north, but at a significantly earlier date than presently considered by archaeologists. Our data suggest that some of the mtDNA lineages found in southern Arabia have persisted in the region since the end of the Last Ice Age. Am J Phys Anthropol 149:291–298, 2012. © 2012 Wiley Periodicals, Inc.     

The Multifaceted Origin of Taurine Cattle Reflected by the Mitochondrial Genome

A Neolithic domestication of taurine cattle in the Fertile Crescent from local aurochsen (Bos primigenius) is generally accepted, but a genetic contribution from European aurochsen has been proposed. Here we performed a survey of a large number of taurine cattle mitochondrial DNA (mtDNA) control regions from numerous European breeds confirming the overall clustering within haplogroups (T1, T2 and T3) of Near Eastern ancestry, but also identifying eight mtDNAs (1.3%) that did not fit in haplogroup T. Sequencing of the entire mitochondrial genome showed that four mtDNAs formed a novel branch (haplogroup R) which, after the deep bifurcation that gave rise to the taurine and zebuine lineages, constitutes the earliest known split in the mtDNA phylogeny of B. primigenius. The remaining four mtDNAs were members of the recently discovered haplogroup Q. Phylogeographic data indicate that R mtDNAs were derived from female European aurochsen, possibly in the Italian Peninsula, and sporadically included in domestic herds. In contrast, the available data suggest that Q mtDNAs and T subclades were involved in the same Neolithic event of domestication in the Near East. Thus, the existence of novel (and rare) taurine haplogroups highlights a multifaceted genetic legacy from distinct B. primigenius populations. Taking into account that the maternally transmitted mtDNA tends to underestimate the extent of gene flow from European aurochsen, the detection of the R mtDNAs in autochthonous breeds, some of which are endangered, identifies an unexpected reservoir of genetic variation that should be carefully preserved.     

Origin of caucasoid-specific mitochondrial DNA lineages in the ethnic populations of the Altai-Sayan region

The data on sequence variation in the first hypervariable segment (HVSI) of human mitochondrial DNA (mtDNA) representing Caucasoid mtDNA lineages in the gene pools of Altaians and Khakassians are presented. Identification of the subgroups of Caucasoid mtDNA lineages found in the gene pools of the ethnic populations of the Altai-Sayan region and the adjacent territories, Altaians, Khakassians, Tuvinians, Buryats, and Yakuts was carried out. All Caucasoid mtDNA lineages belonged to groups H, HV1, J*, J1, J1b1, T1, T4, U1a, U2, U3, U4, U5a1, I, X and N1a. Taking into consideration possible contribution of southern Caucasoid and eastern European components to the formation of the anthropological type of Altai-Sayan ethnic populations, distribution of the revealed Caucasoid mtDNA lineages among the ethnic populations of the Central Asia, Western Asia, Caucasus, and Eastern Europe was examined. The applied approach permitted identification of 60% of mtDNA types the majority of which had southern Caucasoid origin. Less than 10% of mtDNA types were of eastern European origin. The gene pools of Altaians and Khakassians displayed the presence of autochthonous components represented by mtDNA types from subgroups U2 and U4.     

Paternal lineages in Libya inferred from Y‐chromosome haplogroups

Many studies based on genetic diversity of North African populations have contributed to elucidate the modelling of the genetic landscape in this region. North Africa is considered as a distinct spatial‐temporal entity on geographic, archaeological, and historical grounds, which has undergone the influence of different human migrations along its shaping. For instance, Libya, a North African country, was first inhabited by Berbers and then colonized by a variety of ethnic groups like Phoenicians, Greeks, Romans, Arabs and, in recent times, Italians. In this study, we contribute to clarify the genetic variation of Libya and consequently, of North African modern populations, by the study of Libyan male lineages. A total of 22 Y‐chromosome‐specific SNPs were genotyped in a sample of 175 Libyan males, allowing the characterization of 18 Y‐chromosomal haplogroups. The obtained data revealed a predominant Northwest African component represented by haplogroup E‐M81 (33.7%) followed by J(xJ1a,J2)‐M304 (27.4%), which is postulated to have a Middle Eastern origin. The comparative study with other populations (～5,400 individuals from North Africa, Middle East, Sub‐Saharan Africa, and Europe) revealed a general genetic homogeneity among North African populations (F_ST = 5.3 %; P‐value < 0.0001). Overall, the Y‐haplogroup diversity in Libya and in North Africa is characterized by two genetic components. The first signature is typical of Berber‐speaking people (E‐M81), the autochthonous inhabitants, whereas the second is (J(xJ1a,J2)‐M304), originating from Arabic populations. This is in agreement with the hypothesis of an Arabic expansion from the Middle East, shaping the North African genetic landscape. Am J Phys Anthropol 157:242–251, 2015. © 2015 Wiley Periodicals, Inc.     

Phylogeography of mitochondrial DNA and Y-chromosome haplogroups reveal asymmetric gene flow in populations of Eastern India

Polymorphisms in mitochondrial (mt) DNA and Y-chromosomes of seven socially and linguistically diverse castes and tribes of Eastern India were examined to determine their genetic relationships, their origin, and the influence of demographic factors on population structure. Samples from the Orissa Brahmin, Karan, Khandayat, Gope, Juang, Saora, and Paroja were analyzed for mtDNA hypervariable sequence (HVS) I and II, eight Y-chromosome short tandem repeats (Y-STRs), and lineage-defining mutations diagnostic for Indian- and Eurasian-specific haplogroups. Our results reveal that haplotype diversity and mean pairwise differences (MPD) was higher in caste groups of the region (>0.998, for both systems) compared to tribes (0.917-0.996 for Y-STRs, and 0.958-0.988 for mtDNA haplotypes). The majority of paternal lineages belong to the R1a1, O2a, and H haplogroups (62.7%), while 73.2% of maternal lineages comprise the Indian-specific M*, M5, M30, and R* mtDNA haplogroups, with a sporadic occurrence of West Eurasian lineages. Our study reveals that Orissa Brahmins (a higher caste population) have a genetic affinity with Indo-European speakers of Eastern Europe, although the Y-chromosome data show that the genetic distances of populations are not correlated to their position in the caste hierarchy. The high frequency of the O2a haplogroup and absence of East Asian-specific mtDNA lineages in the Juang and Saora suggest that a migration of Austro-Asiatic tribes to mainland India was exclusively male-mediated which occurred during the demographic expansion of Neolithic farmers in southern China. The phylogeographic analysis of mtDNA and Y-chromosomes revealed varied ancestral sources for the diverse genetic components of the populations of Eastern India.     

New haplotype and inter‐strain reproductive compatibility of Wolbachia‐uninfected alfalfa weevil,Hypera postica (Coleoptera: Curculionidae), in Japan

Hypera postica is a univoltine invasive pest of alfalfa, Medicago sativa, in North America. In Japan, H. postica was first found in 1982 from Fukuoka and Okinawa Prefectures and became a serious pest of Chinese milk vetch, Astragalus sinicus, cultivated as a honey source for humans and green manure for rice. In North America, three strains, Western, Eastern and Egyptian, have been identified and the Western strain is infected with Wolbachia, which causes complete inter‐strain reproductive incompatibility. In contrast, only Western and Egyptian strains had been reported throughout Japan and none of the Western strain examined for the Fukuoka populations in northern Kyushu was infected with Wolbachia. First, we screened populations from northern Kyushu collected since 1982 for geographical and chronological distribution of the Eastern strain. The Eastern strain has been found at low frequencies since 1985 and is still present in 2014. Second, we experimentally tested our hypothesis that inter‐strain crosses between uninfected Western‐strain males and Egyptian‐strain females should produce viable offspring. We crossbred virgin adults reared individually from field‐collected larvae and confirmed that the F₁ eggs of crosses between the Western‐strain males and the Egyptian‐strain females develop successfully into larvae.     

Origin of Caucasoid-Specific Mitochondrial DNA Lineages in the Ethnic Groups of the Altai–Sayan Region

The data on sequence variation in the first hypervariable segment (HVSI) of human mitochondrial DNA (mtDNA) representing Caucasoid mtDNA lineages in the gene pools of Altaians and Khakassians are presented. Identification of the subgroups of Caucasoid mtDNA lineages found in the gene pools of the ethnic groups of the Altai–Sayan region and the adjacent territories, Altaians, Khakassians, Tuvinians, Buryats, and Yakuts was carried out. All Caucasoid mtDNA lineages belonged to groups H, HV1, J*, J1, J1b1, T1, T4, U1a, U2, U3, U4, U5a1, I, X and N1a. Taking into consideration possible contribution of southern Caucasoid and eastern European components to the formation of the anthropological type of Altai–Sayan ethnic groups, distribution of the revealed Caucasoid mtDNA lineages among the ethnic groups of the Central Asia, Western Asia, Caucasus, and Eastern Europe was examined. The applied approach permitted identification of 60% of mtDNA types the majority of which had southern Caucasoid origin. Less than 10% of mtDNA types were of eastern European origin. The gene pools of Altaians and Khakassians displayed the presence of autochthonous components represented by mtDNA types from subgroups U2 and U4.     

The Caucasus as an asymmetric semipermeable barrier to ancient human migrations

The Caucasus, inhabited by modern humans since the Early Upper Paleolithic and known for its linguistic diversity, is considered to be important for understanding human dispersals and genetic diversity in Eurasia. We report a synthesis of autosomal, Y chromosome, and mitochondrial DNA (mtDNA) variation in populations from all major subregions and linguistic phyla of the area. Autosomal genome variation in the Caucasus reveals significant genetic uniformity among its ethnically and linguistically diverse populations and is consistent with predominantly Near/Middle Eastern origin of the Caucasians, with minor external impacts. In contrast to autosomal and mtDNA variation, signals of regional Y chromosome founder effects distinguish the eastern from western North Caucasians. Genetic discontinuity between the North Caucasus and the East European Plain contrasts with continuity through Anatolia and the Balkans, suggesting major routes of ancient gene flows and admixture.